The present invention relates to displaying images with digital projectors. Digital projectors are becoming a common tool for both business and entertainment. As these devices become more affordable, many offices and conference rooms have permanently installed digital projectors for sales presentations, reports and conferences. Movie theaters are also realizing the value of digital technology and gradually converting from analog film projectors to their digital counterparts. Further improvements in cost and quality of these devices will make the digital projector a common place addition to home entertainment and theatre systems. Of course, the adoption of this technology would be even faster if the cost and complexity of these systems could be further reduced.
Conventional projector systems use one or more “light valves” for generating different color components in an image. Light valves are also known more generally as spatial light modulators (SLM). For example, a total of three light valves are typically used in projectors displaying images in an RGB (red/green/blue) colorspace—one for each color component. Several technologies for implementing these light valves currently exist in the market. One projector technology creates each color component in the image by passing light through liquid crystal display (LCD) panels. Another projector technology reflects light off digital micromirror devices (DMDs) to create the desired image. Yet another technology operates by reflecting the various color components off a liquid crystal on silicon (LCoS) device. Other emerging projector technologies incorporate grating light valve (GLV), nanotube, or diffractive light device (DLD) technologies for generating the various color components.
In each case, a large part of the projector cost arises from the light-valve components. Light-value components operating with higher resolution and faster switching times allow the projectors to reproduce higher resolution and more realistic images. Of course, fabricating these light valves remains increasingly complex and expensive even though the demand for higher resolution projectors continues to increase. Accordingly, the overall projector cost depends on the number of color components in the color model and the corresponding number of light valves used to represent these color components. For example, conventional high resolution projectors operating in the RGB (red, green and blue) colorspace require three high resolution color valves to generate the desired high resolution image or video on a screen.
It is important for the development of these projectors to further reduce their cost while maintaining or improving the quality and resolution of the images being produced.